GM 9540P PDF
This study is a key reason why GMP became popular as an accelerated laboratory corrosion test for steel. In recent years GMP has been replaced by. of the reference specimens in the as-received condition are in Figure 3. The salt fog test used an abbreviated procedure (Table 3) of the standard GMP test. Find the most up-to-date version of GMP at Engineering
|Published (Last):||27 January 2009|
|PDF File Size:||6.66 Mb|
|ePub File Size:||6.61 Mb|
|Price:||Free* [*Free Regsitration Required]|
Typical Application Originally developed by General Motors the standard has gained popularity for corrosion tests within the automotive industry and has also become the preferred corrosion test of the US Navy. A siphon spray powered by oil-free regulated air or a hand operated pump spray may also be used. Use Option IV – for door detents without weatherseal protection Use Option VI – for door detents with weatherseal protection 1 test cycle is equal to 24 h, 1 phase is equal to 8 cycles.
Typically, the time from ambient to the wet condition should be approximately 1 h and the transition time between wet and dry conditions should be 9540o 3 h. Water fog or visible water droplets on parts – continuous after equilibrium is reached. This process can be aided by using a commercial grade degreaser prior to methanol or acetone clean. To check test progress and assure that the test is being run correctly, assume a linear corrosion rate.
It is the responsibility of the user of this method to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Both are excellent browsers. Prior to start of test, prepare the coupon rack with sufficient coupons to monitor the test 4.
GM P Cyclic Accelerated Corrosion Analysis of Nonchromate Conversion – Google Books
Repeat the cycle daily as necessary until the test duration requirements are met. The number of cycle repeats and therefore the test duration is variable. A phase is made up of a predetermined number of cycles, 8 cycles constitute 1 phase. Ramp time is to be included as part of the specified exposure period.
Sorry. You need to upgrade your browser
This procedure describes 95400p accelerated laboratory corrosion test method to evaluate 5940p and components. If a test is conducted with ramp times different than described above, the number of cycles to reach coupon mass loss targets may increase or decrease. This study is a key reason why GMP became popular as an accelerated laboratory corrosion test for steel.
The weight, in milligrams mgshall be recorded and retained for future reference. In addition to the sample data and test results, reports must indicate the total number of cycles run, any modifications to the test see Appendix Athe Equipment and Test Record Form Appendix B and should include photographic documentation and the coupon mass loss values. If gravelometer exposure is required, test samples not coupons may be exposed to gravelometer testing per GMP before or during exposure.
Also, synergistic effects due to temperature, mechanical and electrical cycling can be comprehended by this test. Garden dusters with vm 8 mm diameter hole for dust application are recommended to achieve the appropriate level of dust application. The temperature and humidity conditions are shown in Table 3. If a recorder is not in use, written documentation should be provided indicating typical steady state conditions and the ramp times between steady states conditions. Test samples shall be representative of production intent.
Garden dusters from the following manufacturers could be modified: The latest revisions include: The solution shall ym sprayed as a mist for example, from a plastic 9450p onto the test samples and coupons.
Originally developed by General Motors the standard has gained popularity for corrosion tests within the automotive industry and has also become the preferred corrosion test of the US Navy.
Coupons consist of See Appendix A for typical modifications. Expected test duration to evaluate functional corrosion is 10 phases.
This method also includes measurement of corrosion creepback from a scribe line, and describes how to evaluate corrosion formation in unscribed areas. The dryoff environment area shall be maintained with sufficient air circulation to prevent temperature stratification, and also allow thorough drying of the material. This method may involve hazardous materials, operations and equipment.
Refer to Table 2 for targeted mass loss values, in milligrams, for various test durations as a function of the coupon’s original thickness.
GMP | Standards | Ascott Analytical
Typically no modifications of this shift. Any option changes not called out specifically in this Appendix must be included on the engineering drawing.
The humidity cabinet shall be as specified by GMP and Table 3. Test durations C and D or any modified test are to be used for validation and development purposes. Ambient Soak 8 h. The test is generally made up of 3 shifts: The mist application occurs while the samples and coupons are in the ambient environment. The test can be started at any time with the understanding that 24 h constitutes 1 cycle.
Additional options can be customized to specific components or subsystems to increase the ability to conduct validation or development testing. Website design by Peter Bourne Communications. If gn actual mass loss does not coincide with the targeted values listed in Table 2 the test should be repeated. To analyze coupons remove 1 coupon from each end of the rack and prepare for weighing and mass loss determination. Wipe the coupons free of grit and weigh to determine the coupon mass loss using the formula: Do not intermix different coupon thickness on the same coupon rack.
950p durations A and B can be used as both QC tests and validation tests depending on the purpose of the test. Modifications to the test may or may not attain equivalent levels of mass loss. Engineering drawings and material specifications that reference this test procedure must specify the test duration, A, B, C or D or the number of test cycles as indicated in Table 1. It requires a 16 h work day or an automatic cycling test chamber. The test sample s shall be inspected for corrosion and photographed at the end of predetermined cycles.
This method does not propose to address all the safety problems associated with its use. At the option of the test requester, the test can be continued throughout weekends to decrease the over all 9540 time.